Follicular dynamics and production of oocytes in young Nellore heifers with energetic supplementation

To verify the effects of energy supplementation and fat on follicular dynamics, metabolic profile and the production of oocytes, 15 young heifers (Bos taurus indicus) with an average age of 14 months and with an initial weight of 256.35 kg were assigned to two treatments according to weight and follicular population as evaluated by ultrasonography: in T1 (1.0 × M), animals received 100% of the energy requirements for maintenance; in T2 (1.7 × M), animals received 170% of the energy requirements for maintenance, achieved by the addition of 200 g of Megalac®. After a period of adaptation to the diet, the treatments, blood collection and follicular aspirations were started using a randomized design. The dry matter intake and weight gain were lower in the 1.0 × M group than in the 1.7 × M group. No differences were found in the plasma progesterone concentrations, albumin, glucose, urea or gonadotropin (FSH and LH) levels between the groups. The mean concentrations of cholesterol were higher in the 1.7 × M group. The total number of small (<4 mm) and medium follicles (4-8 mm) was not altered by the treatments, but the number of small follicles increased on days 1 and 2 of the estrous cycle, with higher values found in the 1.7 × M group. The average of the oocytes also increased (9.50±2.1 and 12.5±4.4 for the 1.0 × M and 1.7 × M groups, respectively). The rapid increase in the amount of energy offered in the diet changes the amount of follicles and oocytes available for follicular aspiration (OPU) in young heifers without changing their metabolic profile.

Dynamics of follicle populations and gonadotropin concentrations in fillies age two to ten months

Follicle populations and concentrations of circulating gonadotropins were studied during age 2-10 months in 10 spring-born pony fillies. Blood sampling and ultrasound scanning were done every 4 days and daily for four 30 day periods. During 5-12 weeks, FSH concentrations were lower in 6 fillies with follicles greater than or equal to 6 mm (mean +/- s.e. 1.4 +/- 0.1 ng/ml) than in 4 fillies with follicles <6 mm (2.8 + 0.3 ng/ml). The diameters and numbers of follicles and gonadotropin concentrations increased progressively during age 2-4 months. A plateau in follicle activity and reduced levels of gonadotropins occurred during 5-7 months. During 8-10 months, follicles grew to >10 mm and gonadotropin concentrations increased. Waves of follicular growth were identified during the 30 day periods by significant increases in the diameter of the 10 largest follicles. The waves did not partition into dominant and subordinate follicles. Results indicated an initial postnatal period of negative ovarian feedback, temporally related changes in gonadotropins and follicles for months 3-10, and development of follicles in waves.

Expression of fibroblast growth factor-8 and regulation of cognate receptors, fibroblast growth factor receptor-3c and-4, in bovine antral follicles

Paracrine cell signaling is believed to be important for ovarian follicle development, and a role for some members of the fibroblast growth factor (FGF) family has been suggested. In the present study, we tested the hypothesis that FGF-8 and its cognate receptors (FGFR3c and FGFR4) are expressed in bovine antral follicles. RT-PCR was used to analyze bovine Fgf8, Fgfr3c and Fgfr4 mRNA levels in oocytes, and granulosa and theca cells. Fgf8 expression was detected in oocytes and in granulosa and theca cells; this expression pattern differs from that reported in rodents. Granulosa and theca cells, but not oocytes, expressed Fgfr3c, and expression in granulosa cells increased significantly with follicle estradiol content, a major indicator of follicle health. Fgfr4 expression was restricted to theca cells in the follicle, and decreased significantly with increasing follicle size. To investigate the potential regulation of Fgfr3c expression in the bovine granulosa, cells were cultured in serum-free medium with FSH or IGF-I; gene expression was upregulated by FSH but not by IGF-I. The FSH-responsive and developmentally regulated patterns of Fgfr3c mRNA expression suggest that this receptor is a potential mediator of paracrine signaling to granulosa cells during antral follicle growth in cattle.

Prolactin and zinc in dialysis patients

The objectives of the present study were to investigate the frequencies of hyperprolactinemia and hypozincemia in patients undergoing hemodialysis (HD) or continuous ambulatory peritoneal dialysis (CAPD), the associations between blood levels of zinc (Zn2+) and hormones, and dietary zinc intake amount and its relation to zincemia. We studied 28 patients (14 HD and 14 CAPD) who had their blood levels of Zn2+, prolactin (PRL), parathyroid hormone (PTH), and gonadotropins (LH, FSH) evaluated. Thirteen patients had dietary nutrient amounts evaluated from a 3-d nutritional record. Hyperprolactinemia occurred in 29% patients (HD = CAPD), hypozincemia in 62% (20% HD and 42% CAPD), and low dietary Zn2+ intake in 90% of patients. No correlation among blood concentration of Zn2+ and PRL, PTH, LH, and FSH were observed in the two modalities of dialysis or between zincemia and Zn2+ ingestion. We concluded that the occurrence of hyperprolactinemia and hypozincemia were not related to dialysis modality and that zincemia did not reflect the observed low dietary intake of Zn2+.

Benefits of soy germ isoflavones in postmenopausal women with contraindication for conventional hormone replacement therapy

Objective: To evaluate the effects of isoflavones on vasomotor symptoms and blood lipids in postmenopausal women with contraindication for conventional hormone replacement therapy (HRT). Methods: This prospective, double-blind and placebo-controlled study included 50 postmenopausal women randomly divided into two groups: 25 women on soy germ isoflavones (60 mg per day, capsules) and 25 women on placebo. Inclusion criteria included: non-vegetarian, non-asian women whose last menstruation dated at least 12 months prior to the beginning of the study, With FSH > 40 mIU/ml, hot flushes and contraindication for HRT, not using tamoxifen or antibiotic and no disease of the gastrointestinal tract. For 6 months, the Kupperman menopausal index (KMI), the vaginal cytological maturation value (MV) and both hormonal and lipid profiles were assessed. The t-test and analysis of variance (ANOVA) were employed to compare the two groups. Results: In both groups, a decreased KI rate was observed. However, isoflavone was significantly superior to placebo in reducing hot flushes (44% versus 10%, respectively) (P < 0.05). After 6 months, the isoflavone group showed increased estradiol levels with unchanged FSH, LH, and vaginal cytology, and a reduction of 11.8% in LDL and an increase of 27.3% in HDL (P < 0.05). In the placebo group, just a reduction in MV was observed after 6 months (P < 0.05). Conclusions: Soy germ isoflavone exerted favorable effects on vasomotor symptoms and lipid profile, showing itself to be an interesting alternative therapy for the postmenopausal women with contraindication for conventional HRT. (C) 2003 Elsevier B.V.. All rights reserved.

Risk factors for amenorrhea in juvenile systemic lupus erythematosus (JSLE): a Brazilian multicentre cohort study

We evaluated the prevalence and clinical associations of amenorrhea in 298 female juvenile systemic lupus erythematosus (JSLE) patients (ACR criteria) followed in 12 Brazilian Paediatric Rheumatology centres. Amenorrhea was observed in 35 patients (11.7%) with a mean duration of 7.2 +/- 3.6 months. The hormones were performed in 32/35 patients and none of them had FSH and LH levels above and estradiol below the normal range according to pubertal changes. JSLE patients with amenorrhea were younger (15.04 +/- 2.5 versus 17.8 +/- 3.1 years; P = 0.001), and had a shorter period of time between menarche and current age (3.4 +/- 2.9 versus 6.7 +/- 5.4 years; P = 0.001). Interestingly, the frequency, cumulative dose, number of pulses and duration of intravenous cyclophosphamide treatment were alike in patients with and without amenorrhea (P > 0.05). In contrast, patients with amenorrhea had significantly higher SLEDAI (P = 0.01) and SLICC/ACR-DI (P = 0.024) scores compared to those without this condition. Independent risk factors identified by multivariate analysis were higher SLEDAI (OR=1.059; CI=1.004-1.116; P=0.034) and SLICC/ACR-DI (OR=2.125; IC = 1.373-3.291; P = 0.001) scores. Our data suggest that in spite of imummosuppressive therapy, JSLE patients have an adequate ovarian follicular reserve and amenorrhea is particularly associated with disease activity and damage.

Effects of dominant follicle aspiration and treatment with recombinant bovine somatotropin (BST) on ovarian follicular development in Nelore (Bos indicus) heifers

Follicle ablation has been recognized as an efficient method of follicular wave synchronization. Treatment with recombinant bovine somatotropin (BST) has been shown to enhance follicular development in <(Bos taurus)under bar>. This experiment assessed the effects of these treatments in Nelore (<(B. indicus)under bar>) heifers. Eight cycling Nelore heifers were randomly assigned to 3 different treatments. on Day 2 of a synchronized cycle (Day 0 = day of ovulation), heifers assigned to Treatments 1 and 2 received 2 mL of saline, whereas heifers assigned to Treatment 3 received 320 mg of BST. on Day 5, the first-wave dominant follicle was ablated by ultrasoundguided transvaginal aspiration in heifers in Treatments 2 and 3, and all heifers received an injection of prostaglandin on Day 11. Aspiration of the dominant follicle advanced and synchronized (P < 0.05) the day of second-wave emergence (6.9 +/- 0.1 vs. 8.4 +/- 0.4) and the day of the pre-wave FSH peak (6.0 +/- 0.0 vs. 6.9 +/- 0.4), and increased FSH peak concentrations (381 +/- 21 vs. 292 +/- 30; pg/mL; P < 0.01). Recombinant bovine somatotropin treatment caused a two-fold increase in plasma insulin-like growth factor-I (IGF-I) concentrations (P < 0.001) and resulted in a 36% increase in the number of small follicles (<5 mm; P < 0.001) compared with saline-treated heifers. In summary, in agreement with previous reports on <(B. taurus)under bar>, dominant follicle aspiration synchronized ovarian follicular development, and BST treatment increased peripheral concentrations of IGF-I in Nelore heifers. Recombinant bovine somatotropin also increased the number of small follicles, but this response appeared to be inferior to that reported for <(B. taurus)under bar>. (C) 2000 by Elsevier B.V.

Enhanced ERbeta immunoexpression and apoptosis in the germ cells of cimetidine-treated rats

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Ultrastructural analysis of bovine oocytes from ovarian follicles with different diameters

In vitro embryo production is an important technique for facilitating the reproduction of animals with high genetic merit. The greatest challenge for the reproducibility of this technique is the quality of the oocyte that is submitted for in vitro maturation. The aim of this work was to evaluate the ultrastructural characteristics of oocytes from follicles of different diameters using transmission electron microscopy. The animals were divided into 2 groups and were given a single i.m. injection of 250 IU FSH (Pluset, Serono, Italy). To synchronize the follicular growth, all follicles > 2 mm were aspirated during the estrous cycle, which was considered day zero (D0). Group 1 (G1; n = 4) received FSH on day 1 (D1), and the 2- to 5-mm follicles were aspirated on day 2 (D2). The animals in group 2 (G2; n = 5) received FSH on day 2 (D2), and their 10- to 15-mm follicles were aspirated on day 5 (D5). After aspiration, the oocytes from both groups were fixed and prepared for ultrastructural analysis. The oocytes analyzed from both groups had similar ultrastructural characteristics. The presence and distribution of organelles in the cytoplasm of the oocytes did not differ between groups, suggesting that, in relation to the ultrastructural characteristics, oocytes from 2 to 5 mm and 10 to 15 mm follicles are similar.

Ovarian response to superovulation in Nelore cows (Bostaurusindicus L.)

Superovulation was induced in 15 Nelore cows with porcine follicle stimulating hormone (FSH-P) or pregnant mare serum gonadotropin (PMSG), and embryos were collected to compare the response of this breed of cattle to these hormones. FSH-P was given in 30-and 40-mg doses for 5 d as a single daily injection or fractionated into two daily injections. PMSG was given in doses of 1000 and 2000 IU. The animals were killed immediately after embryo collection and the ovaries and genitalia were examined clinically. PMSG proved to be more effective in inducing superovulation than FSH-P, probably because PMSG caused no stress since it was administered as a single dose. No differences were observed between the 30-and 40-mg dose of FSH-P or between the application as a single or fractionated dose. Differences did occur, however, between the number of ovulations and embryos obtained at each collection. On the basis of postmortem analysis, we concluded that lack of egg uptake by the infundibulum had occurred in cases of increased ovulation, with excessive increase in volume of the ovary. We also recommend using smaller doses of FSH-P and suggest that avoiding stress in handling is essential for a good response to hormonal stimulation by Zebu cattle. © 1986.

Role of luteinizing hormone in follicle deviation based on manipulating progesterone concentrations in mares

The effects of several doses of progesterone on FSH and LH concentrations were used to study the role of the gonadotropins on deviation in growth rates of the two largest follicles during the establishment of follicle dominance. Progesterone was given to pony mares at a daily dose rate of 0 mg (controls), 30 mg (low dose), 100 mg (intermediate dose), and 300 mg (high dose). All follicles ≥ 6 mm were ablated at Day 10 (Day 0 = ovulation) to initiate a new follicular wave; prostaglandin F(2α) was given to induce luteolysis, and progesterone was given from Days 10 to 24. The low dose did not significantly alter any of the ovarian or gonadotropin end points. The high dose reduced (P < 0.05) the ablation-induced FSH concentrations on Day 11. Maximum diameter of the largest follicle (17.2 ± 0.6 mm) and the second- largest follicle (15.5 ± 0.9 mm) in the high-dose group was less (P < 0.04) than the diameter of the second-largest follicle in the controls (20.0 ± 1.0 mm) at the beginning of deviation (Day 16.7 ± 0.4). Thus, the growth of the two largest follicles was reduced by the high dose, presumably through depression of FSH, so that the follicles did not attain a diameter characteristic of deviation in the controls. The intermediate dose did not affect FSH concentrations. However, the LH concentrations increased in the control, low, and intermediate groups, but then decreased (P < 0.05) in the intermediate group to pretreatment levels. The LH decrease in the intermediate group occurred 2 days before deviation in the controls. The maximum diameter of the largest follicle was less (P < 0.0001) in the intermediate group (27.3 ± 1.8 mm) than in the controls (38.9 ± 1.5 mm), but the maximum diameter of the second-largest follicle was not different between the two groups (19.0 ± 1.1 vs. 20.3 ± 1.0 mm). Thus, the onset of deviation, as assessed by the second-largest follicle, was not delayed by the decrease in LH. Diameter of the largest follicle by Day 18 in the intermediate group (23.1 ± 1.6 mm) was less (P < 0.05) than in the controls (28.0 ± 1.0 mm). These results suggest that circulating LH was not involved in the initiation of dominance (inhibition of other follicles by the largest follicle) but was required for the continued growth of the largest follicle after or concurrently with its initial expression of dominance.

Inhibin B and the ovarian follicular reserve

Inhibins are dimeric glycoproteins composed of an α-subunit and a βA-subunit (inhibin A) or βB-subunit (inhibin B), which inhibits pituitary gonadotropin secretion of FSH. The inhibin B is a product of the cohort of antral follicles. The ovarian follicle number decrease steadily as a function of increasing age, with consequent falls in the levels of inhibin B and increase of FSH levels. It is sufficient to maintain ovulatory function and continued secretion of estradiol. Elevated FSH levels seem to occur late in the sequence of events associated with ovarian failure. The inhibin B, produced by granulosa cells, is the earliest marker of the decline in ovarian follicular reserve across reproductive aging.

Embryo recovery and pregnancy rates after the delay of ovulation and fixed time insemination in superstimulated beef cows

The aim of this study was to evaluate the effect of delaying ovulation subsequent to superstimulation of follicular growth in beef cows (Bos indicus) on embryo recovery rates and the capacity of embryos to establish pregnancies. Ovulation was delayed by three treatments using either progesterone (CIDR-B®) or a GnRH agonist (deslorelin). Multiparous Nelore cows (n = 24) received three of four superstimulation treatments in an incomplete block design (n = 18 per group). Cows in Groups CTRL, P48 and P60 were treated with a CIDR-B device plus estradiol benzoate (EB, 4 mg, i.m.) on Day-5, while cows in Group D60 were implanted with deslorelin on Day-7. Cows were superstimulated with FSH (Folltropin-V® 200 mg), from Day 0 to 3, using twice daily injections in decreasing amounts. All cows were treated with a luteolytic dose of prostaglandin on Day 2 (08:00 h). CIDR-B devices were removed as follows: Group CTRL, Day 2 (20:00 h); Group P48, Day 4 (08:00 h); Group P60, Day 4 (20:00 h). Cows in Group CTRL were inseminated at 10, 20 and 30 h after first detected estrus. Ovulation was induced for cows in Group P48 (Day 4, 08:00 h) and Groups P60 and D60 (Day 4, 20:00 h) by injection of LH (Lutropin®, 25 mg, i.m.), and these cows were inseminated 10 and 20 h after treatment with LH. Embryos were recovered on Days 11 or 12, graded and transferred to synchronized recipients. Pregnancies were determined by ultrasonography around Day 100. Data were analyzed by mixed procedure, Kruskal-Wallis and Chi-square tests. The number of ova/embryos, transferable embryos (mean ± S.E.M.) and pregnancy rates (%) were as follows, respectively: Group CTRL (10.8 ± 1.8, 6.1 ± 1.3, 51.5), P48 (12.6 ± 1.9, 7.1 ± 1.0, 52.3), P60 (10.5 ± 1.6, 5.7 ± 1.3, 40.0) and D60 (10.3 ± 1.7, 5.0 ± 1.2, 50.0). There were no significant differences among the groups (P > 0.05). It was concluded that fixed time AI in association with induced ovulation did not influence embryo recovery. Furthermore, pregnancy rates in embryos recovered from cows with delayed ovulation were similar to those in embryos obtained from cows treated with a conventional superstimulation protocol. © 2002 Elsevier B.V. All rights reserved.

Inhibin B and ovarian function after total abdominal hysterectomy in women of reproductive age

The aim of this prospective study was to assess ovarian function using clinical and endocrine parameters in women of reproductive age who underwent total abdominal hysterectomy. Sixty-one women, aged ≤ 40 years, were allocated into two groups: group 1, consisting of 31 patients who had hysterectomy, and group 2, consisting of 30 normal women. Inclusion criteria were normal ovarian function at baseline, normal body weight, no hormonal diseases and basal follicle stimulating hormone (FSH) level of < 15 mIU/ml. FSH, luteinizing hormone (LH), estradiol and inhibin B levels as well as maturation value (MV) were measured by vaginal cytology on three occasions: baseline, and 6 and 12 months after hysterectomy. Analysis of variance, the Friedman test, Mann-Whitney test and t-test statistics were employed to compare the two groups. At baseline the groups were homogeneous. At months 6 and 12, hysterectomized women showed decreased median values of inhibin B, increased median values of estradiol (p < 0.05), unchanged median values of FSH and LH, and decreased median values of MV (p < 0.05). In the hysterectomy group, 12.9% (4/31) of the patients had FSH levels of > 40 mIU/ml, estradiol of < 20 pg/ml and inhibin B of < 5 ng/ml, compatible with ovarian failure. In the control group, all the parameters studied remained unchanged. These results suggest that total abdominal hysterectomy accelerates the decline in ovarian function in women of reproductive age.

Diagnosis of 5α-reductase type 2 deficiency: Contribution of anti-Müllerian hormone evaluation

Aim: To evaluate anti-Müllerian hormone (AMH) levels in patients with clinical and molecular diagnosis of 5α-reductase 2 deficiency. Patients and methods: Data from 14 patients whose age ranged from 21 days to 29 years were analyzed according to age and pubertal stage. Sexual ambiguity was rated as Prader III in 11 patients. LH, FSH, testosterone (T), dihydrotestosterone (DHT) and AMH serum levels were measured in all but two patients, who had been previously submitted to gonadectomy; T and DHT were also measured in 20 age-matched controls. Results: Gonadotropin levels were normal in all but one patient who retained gonads (six of whom had reached puberty) and T/DHT ratio was elevated in all patients when compared to controls. All prepubertal patients had AMH levels < -1 SD for age, while most pubertal patients had AMH levels compatible with pubertal stage. Conclusions: Prepubertal patients with 5α-reductase 2 deficiency have AMH values in the lower part of the normal range. These data indicate that T does not need to be converted to DHT to inhibit AMH secretion by Sertoli cells. © Freund Publishing House Ltd., London.